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Abstract:

A dishwasher includes a shiftable rack provided with multiple, distinct
washing fluid spray arms connected to a common, rack supported manifold.
When the rack is shifted to a retracted position within a tub of the
dishwasher, the manifold mates with a coupling of a fluid distribution
system including a multi-tube feed arrangement configured to selectively
distribute washing fluid from a pump assembly to the multiple spray arms.

Claims:

1-14. (canceled)

15. A method of distributing washing fluid from a pump assembly to first
and second spray arms attached to a rack for movement with the rack
between a retracted, operational position and an extended, kitchenware
access position relative to a tub of a dishwasher comprising: directing a
first flow of washing fluid from the pump assembly to a first tube,
through a manifold fixed for movement with the rack, to the first spray
arm; and directing a second flow of washing fluid from the pump assembly
to a second tube, through the manifold, to the second spray arm.

16. The method of claim 15, further comprising: mating the manifold with
a coupling, which is fixed relative to the tub and fluidly connected with
each of the first and second tubes, upon positioning of the rack in the
retracted, operational position.

17. The method of claim 16, further comprising: deflecting flapper valves
provided in the manifold upon mating the manifold with the coupling.

18. The method of claim 15, wherein the first spray arm rotates relative
to the rack upon directing the first flow of washing fluid to the first
spray arm, and the second spray arm sprays washing fluid from a fixed
position relative to the rack upon directing the second flow of washing
fluid to the second spray arm.

19. The method of claim 15, further comprising: vertically repositioning
a height of the rack within the tub between an upper operational position
and a lower operational position, and interconnecting the first and
second tubes to the first and second upper spray arms through the
manifold in each of the upper and lower operational positions.

20. The method of clam 15, wherein directing the first flow of washing
fluid from the pump assembly to the first tube further functions to
deliver a portion of the washing fluid to a third spray arm mounted above
the rack.

Description:

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention pertains to the art of dishwashers and, more
particularly, to a dishwasher including a system for delivering washing
fluid to at least one lower spray arm associated with a lower rack and
multiple upper spray arms carried by an upper rack.

[0003] 2. Description of the Related Art

[0004] In the art of dishwashers, it is known to provide multiple,
vertically spaced spray arms within a single wash tub in order to enhance
the spray patterns of washing fluid. For use with these various spray arm
arrangements, many different types of fluid distribution systems have
been developed to address different problems or to provide a dishwasher
with specific functionality. For instance, in order to increase the
distribution of washing fluid, it is known in the art to provide a
dishwasher tub with a lower, rotatable spray arm mounted for rotation
below a lower rack, an upper, rotatable spray arm mounted above an upper
rack and an intermediate, rotatable spray arm provided below the upper
rack. In such an arrangement, the intermediate spray arm is mounted to
the upper rack for concurrent movement into and out of the tub of the
dishwasher. To accommodate this movement, a fluid connection must be made
to the intermediate spray arm upon retraction of the upper rack into the
tub.

[0005] If the upper rack is vertically adjustable, additional provisions
must be made to provide the necessary fluid connection when the upper
rack is in each of the various vertical orientations. In general, this
adjustability function is accomplished by fixedly mounting a valve and
manifold assembly to the tub at the height of the upper rack, with the
manifold including multiple ports which can be alternatively accessed to
provide the requisite washing fluid flow to the intermediate spray arm.

[0006] As an additional consideration, it can be desirable to provide a
flow control system to regulate the flow timing to each of the spray
arms. For instance, based on water pressure or other reasons, it may not
be feasible to provide flow to each of the spray arms simultaneously. If
this is the case, separate and distinct fluid conduits and/or complicated
valving may be employed in combination with a water diverter mechanism in
order to selectively direct the washing fluid to the lower wash arm, the
upper wash arm, the intermediate wash arm or certain combinations of the
wash arms.

[0007] Simply stated, regardless of these known systems, there is still
seen to exist a need to further modify the parameters and configuration
of an overall washing system within a dishwasher to provide a spray flow
and coverage that will enhance the overall cleaning operation being
performed.

SUMMARY OF THE INVENTION

[0008] The present invention provides for an enhanced dishwasher washing
system including a movable rack supporting multiple, distinct spray arms.
That is, in addition to the potential for lower and upper spray arms, the
dishwasher includes an upper rack carrying multiple, distinct washing
fluid spray arms. In a preferred embodiment, the upper rack spray arms
include a rotatable spray arm suspended beneath the upper rack and a
bifurcated spray arm unit which establishes front spray arms, side spray
arms or a combination of front and side spray arms. A fluid distribution
system, including a multi-tube feed arrangement in combination with a
rack supported manifold, is employed to provide for selective
distribution of washing fluid to the upper rack spray arms.

[0009] During operation of the dishwasher, a diverter valve mechanism is
employed to selectively deliver washing fluid from a recirculation pump
assembly to the various spray arms of the dishwasher. In connection with
the upper rack, the diverter valve mechanism directs washing fluid to a
select one of the feed tubes, with one feed tube directing washing fluid
through the manifold to the rotatable spray arm and another feed tube
directing washing fluid through the manifold to the front and/or side
spray arms. The manifold is internally divided to establish a split
chamber and includes multiple ports to maintain separate the fluid flow
from the recirculation pump assembly to the distinct spray arms. In a
preferred embodiment, the manifold actually includes upper and lower sets
of ports to also accommodate vertical adjustment of the upper rack, while
still providing for the separate flow patterns. Distribution control is
based on both washing cycle selections and cycle timing.

[0010] Additional objects, features and advantages of the present
invention will become more readily apparent from the following detailed
description of preferred embodiments when taken in conjunction with the
drawings wherein like reference numerals refer to corresponding parts in
the several views.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 is a perspective view of a dishwasher incorporating a
multi-feed washing system constructed in accordance with the present
invention;

[0012] FIG. 2 is a perspective view of feed tube connections to a
distribution cap of a recirculation pump assembly of the dishwasher of
FIG. 1;

[0013] FIG. 3 is a perspective view of an upper rack of the dishwasher of
FIG. 1 in combination with a fluid distribution system, including a rack
supported manifold for distributing washing fluid from the multi-feed
tubes of FIG. 2 to multiple spray arms carried by the rack;

[0014] FIG. 4 is an exploded view of fluid distribution system and
multiple spray arms of FIG. 3;

[0015] FIG. 5 is a rear view of a section of the multi-feed tubes having a
manifold connection coupling attached thereto;

[0016] FIG. 6 is a rear perspective view of the manifold and an associated
spray arm;

[0017] FIG. 7 illustrates a preferred mounting of a bifurcated spray arm
portion of the multiple spray arms of FIG. 4 to a front portion of the
rack; and

[0019] With initial reference to FIG. 1, a dishwasher constructed in
accordance with the present invention is generally indicated at 2. As
shown, dishwasher 2 includes a tub 5, which is preferably injection
molded of plastic, so as to include integral bottom, side, rear and top
walls 8-12 respectively. Within the confines of walls 8-12, tub 5 defines
a washing chamber 14 within which soiled kitchenware is adapted to be
placed on a lower dish rack 15 and/or an adjustable upper rack 16 which
is mounted through an adjustment mechanism 17 for vertically shifting
dish rack 16 between a first or lowered position and a second or raised
position. As the particulars of adjustment mechanism 17 do not form part
of the invention, they will not be described further here. Instead, an
adjustment mechanism known in the art can be employed, such as that
disclosed in U.S. Pat. No. 7,410,228 incorporated herein by reference. As
shown in this figure, tub 5 pivotally supports a door 20, having an
exterior panel 22 and an interior panel 23, used to seal washing chamber
14 during a washing operation.

[0020] In a manner known in the art, upper rack 16 is horizontally
shiftable between a first, retracted position wherein upper rack 16 is
entirely within the confines of washing chamber 14 as shown in FIG. 1 and
a second, extended position, wherein upper dish rack 16 projects, at
least partially outward, from washing chamber 14. Toward that end,
dishwasher 2 is provided with extensible support members, one of which is
indicated generally at 26. In a similar manner, lower dish rack 15 is
selectively, horizontally shiftable between retracted and extended
positions. However, when in the extended position, lower dish rack 15
rests upon an open door 20 on guide elements (not separately labeled)
formed on interior panel 23.

[0021] Disposed within tub 5 and, more specifically, mounted within a
central opening formed in bottom wall 8 of tub 5, is a pump assembly 30
constructed in a manner known in the art, such as that represented by
U.S. Pat. No. 7,146,992 which is incorporated herein by reference.
Extending about a substantial portion of pump assembly 30, at a position
raised above bottom wall 8, is a heating element 44. In a manner known in
the art, heating element 44 preferably takes the form of a sheathed,
electric resistance-type heating element. In general, pump assembly 30 is
adapted to direct washing fluid to a lower spray arm 47, an intermediate
spray arm 48 and an upper arm 49 as will be detailed fully below.

[0022] For the sake of completeness, dishwasher 2 also has associated
therewith a drain hose 85 including at least one corrugated or otherwise
curved portion 89 that extends about an arcuate hanger 92 provided on an
outside surface of side wall 10. Drain hose 85 is also preferably secured
to tub 5 through various clips, such as that indicated at 94. In this
manner, an upper loop is maintained in drain hose 85 to assure proper
drainage in a manner known in the art. As the exact structure and
operation of pump assembly 30 of dishwasher 2 is not part of the present
invention, it will not be discussed further herein. Instead, the present
invention is directed to particulars of the washing system associated
with upper rack 16. More specifically, the invention is concerned with
the manner in which washing fluid is delivered from pump assembly 30
through a fluid distribution system to spray arms 47-49, as well as an
additional spray arm 97 carried by rack 16.

[0023] In connection with the flow of washing fluid, FIG. 2 depicts an
enlarged view of a distribution head 100 provided atop pump assembly 30.
As shown, distribution head 100 includes a plate 102 beneath which are
provided a plurality of circumferentially spaced fins, one of which is
indicated at 104. Fins 104 are configured to be aligned with cut-outs
(not shown) provided in pump assembly 30 and enable distribution head 100
to be mounted atop pump assembly 30 through a twist lock arrangement.
More importantly, distribution head 100 is shown to include a first
outlet 107 having a head portion 108 to which spray arm 47 is adapted to
be rotatably mounted in a manner known in the art. Head portion 108
defines a flow passage 110 for directing a flow of washing fluid
generated by pump assembly 30 to spray arm 47.

[0024] Distribution head 100 also has associated therewith a second outlet
112 and a third outlet 115. A first tube 118 of a multi-tube feed
arrangement generally indicated at 120 is attached to second outlet 112
and is also adapted to receive a flow of washing fluid from pump assembly
30. Multi-tube feed arrangement 120 also includes a second tube 122 that
is shown to be interconnected to first tube 118 through a web 124.
Preferably, first and second tubes 118 and 122 are formed together to
establish a unitary conduit assembly even though first tube 118 and
second tube 122 are completely separate and distinct with respect to
their isolated fluid flows. Mounted to an end of second tube 122 is a
connector 128 that is part of a rotatable leg 130 which fluidly
interconnects second tube 122 to third outlet 115 of distribution head
100.

[0025] During overall assembly, multi-tube feed arrangement 120 is
connected to distribution head 100 with first tube 118 being initially
connected to second outlet 112 and then leg 130 is rotated in order to
register with third outlet 115. In any case, at this point, it should be
recognized that distribution head 100 provides for three distinct flows
there through in connection with first, second and third outlets 107, 112
and 115. As will be detailed more fully below, the flow to each of first,
second and third outlets 107, 112 and 115 is regulated during a washing
operation such that the flows are not simultaneously provided in order to
enhance flow pressure. In connection with regulating these various flows,
a diverter valve unit, generally indicated at 126, is provided beneath
distribution head 100 and incorporated into pump assembly 30. In general,
the function and operation of a diverter valve unit in the dishwasher art
is known as evidenced by the disclosure in U.S. Pat. No. 7,914,625,
incorporated herein by reference. Therefore, as the specific details of
the operation of diverter valve unit 126 is not considered part of the
present invention such that it will not be further discussed herein.

[0026] With reference to FIGS. 1 and 3, multi-tube feed arrangement 120
leads away from pump assembly 30 towards rear wall 11 of tub 5 and
extends up rear wall 11. Above upper rack 16, second tube 122 terminates
and first tube 118 of multi-tube feed arrangement 120 transitions into an
upright tube extension 132 and a horizontal tube extension 133 which
project above upper rack 16. Rotatably attached to horizontal tube
extension 133 is upper spray arm 49. As best shown in FIG. 3, upper rack
16 includes a base 136, a front wall portion 139, rear wall portion 140
and side wall portions 141 and 142. In the embodiment shown, upper rack
16 is formed from a plurality of interconnected, plastic coated wires,
one of which is indicated at 145 to be part of front wall portion 139. At
this point, it should be realized that the actual layout of wires 145 for
upper rack 16 can greatly vary in accordance with the present invention
and such types of wire racks are widely known in the art.

[0027] As shown in each of FIGS. 3-5, first tube 118 and second tube 122
lead to upright tube extension 132 through a junction 152. Junction 152
is provided with a pair of ports 154 and 155 (see FIG. 4) which open up
to first tube 118 and second tube 122 respectively. Secured at junction
152 is a coupling 158 having a front plate 160 from which project port
extensions 161 and 162. Coupling 158 also includes side plate portions,
one of which is indicated at 164, as well as a pair of spaced ears or
guide pins 168 and 169. In connection with securing coupling 158 to
junction 152, multi-tube feed arrangement 120 is preferably formed with a
plurality of vertically spaced, side locking tabs, one of which is
indicated at 172, with tabs 172 aligning with respective openings 174
provided in side plate portions 164 of coupling 158. In this manner,
coupling 158 can be snap-connected about junction 152, with tabs 172
extending into openings 174 (see FIG. 5). This locking arrangement, in
combination with the manner in which coupling 158 conforms to the shape
of junction 152, retains coupling 158 on junction 152, with port
extensions 161 and 162 being aligned with ports 154 and 155 respectively.

[0028] Mounted to upper rack 16 for movement between the retracted and
extended positions relative to tub 5 is a manifold 180. As shown best in
FIG. 4, manifold 180 includes a body 182 provided with frontal ports 185
and 186. Interposed between body 182 of manifold 180 and coupling 158 is
a flapper valve member 189. Basically, flapper valve member 189 is
received within body 182 of manifold 180 and includes a plurality of
flapper valves, one of which is indicated at 190. In general, flapper
valve member 189 constitutes a flexible rubber sheet with flapper valves
190 being defined by portions of the flexible material which have been
cut around its circumference except for along a short segment which
enables the valve to be biased closed, yet move into body 182 of manifold
180 when engaged by a respective port extension 161, 162 as will become
more fully evident below. To retain flapper valve member 189 in place
within body 182, a cover member 195 is provided. Cover member 195 is
preferably constituted by a hard plastic piece having a plurality of
openings, one of which is indicated at 197, with openings 197 being
aligned with flapper valves 190.

[0029] Extending from port 186 of manifold 180 is a first upper spray arm
202. At a terminal end (not labeled) of first upper spray arm 202 is
arranged a head 204 to which is rotatably attached intermediate spray arm
48. Head 204 is also provided with an associated mounted bracket 209. As
will be discussed more fully below, mounting bracket 209 is utilized in
connection with attaching manifold 180 to upper rack 16 for concurrent
movement. For this purpose, mounting bracket 209 includes a frontal slot
210 defined between upper and lower flanges (not labeled) and first upper
spray arm 202 is provided with an upstanding locator flange 211 as also
discussed further below. Also extending from body 182 of manifold 180 is
a second spray arm generally indicated at 213. More specifically, in the
embodiment shown, second spray arm 213 is formed from multiple,
interconnected pieces and includes a flow tube 216 that extends about and
is coupled to port 185 of manifold 180 and leads to a T-connector 219.
With this arrangement, the flow in flow tube 216 is bifurcated so as to
flow in opposing directions towards tubular ends 222 and 223 of
T-connector 219. T-connector 219 is also formed with a mounting bracket
225 including a hanger element 227. Designed to be fluidly connected to
tubular ends 222 and 223 are a pair of sub-arm assemblies 231 and 232. As
each sub-arm assembly 231, 232 is identically constructed, details will
now be made of sub-arm assembly 231 and it is to be understood that
sub-arm assembly 232 has corresponding structure. As clearly shown in
FIG. 4, sub-arm assembly 231 includes an angled flow tube 235 having a
first leg 237 and a second leg 238. Given the generally rectangular
configuration of upper rack 16, first leg 237 and second leg 238 are
generally arranged perpendicular to one another. Certainly, other
configurations are possible in order to conform to a desired shape of
upper rack 16 and to enhance fluid flow. As also shown in these figures,
an exterior corner nozzle 242 is provided at the junction between first
leg 237 and second leg 238. Additional details of exterior corner nozzle
242 will be presented further herein. Sub-arm assembly 231 also includes
a transition tube 244 having a first end 246 which is connected to second
leg 238 and a second end 247 which is angled relative to first end 246
and preferably redirects washing fluid upward. Second end 247 has mounted
thereto an interior corner nozzle 249 which will also be detailed further
below.

[0030] Reference will now be made to FIG. 6 in describing additional
structural details of manifold 180, first upper spray arm 202 and
mounting bracket 209. As shown, a rear portion of body 182 includes an
internal divider 252 having a central boss 254 for the mounting of cover
member 195. Body 182 is also provided with a series of lobes 256-259, as
well as side regions 261 and 262 which are substantially flat and are
defined by spaces between lobes 256 and 259 and lobes 257 and 258
respectively. At mounting bracket 209, which is spaced from body 182 of
manifold 180 by first upper spray arm 202, is provided with a pair of
spaced, upper support members 265 and 266. Each of support members 265
and 266 is adapted to engage a respective wire of upper rack 14 in
connection with mounting manifold 180 and first upper spray arm 202 to
upper rack 16. Below support member 266, mounting bracket 209 includes a
concave portion 268 which receives flow tube 216 of second spray arm 213.

[0031] In connection with describing the mounting of first upper spray arm
202 and second upper spray arm 213 to upper rack 16, reference will
initially be made to FIGS. 3, 4 and 6. As previously indicated, first
upper spray arm 202 is arranged beneath upper rack 16 as clearly shown in
FIG. 3. Mounting bracket 209 engages with wires (not labeled) of upper
rack 16, with one wire extending between side wall portions 141 and 142
being received within slot 210 of mounting bracket 209, while additional
portions of the same wire are received by support members 265 and 266
(see FIG. 3). In this manner, potential forward movement of first upper
spray arm 202 and manifold 180 towards front wall portion 139 is
prevented. Thereafter, first upper spray arm 202 and manifold 180 are
swung such that additional wires of upper rack 16 clip into recessed
regions 269 and 270 formed in body 182. At the same time, locating flange
211 extends along a wire of base 136. With this overall mounting
arrangement, head 204 can support intermediate spray arm 48 for rotation.
At the same time, flow tube 216 has an end extending about port 185,
extends within concave portion 268 of mounting bracket 209 and is fluidly
connected with T-connector 219. More specifically, as best shown in FIG.
7, T-connector 219 includes a tube connector 274 which receives flow tube
216. Projecting out from tube connector 274 is a pair of space
projections 277 and 278 which extend about another wire (not labeled) of
upper rack 16 as clearly shown in this figure. To further mount second
spray arm 213, hanger element 227 of mounting bracket 225 is hung over
wire 145 of upper rack 16.

[0032] At this point, it should be readily understood that it is simply
important that each of manifold 180, first upper spray arm 202 and second
spray arm 213 be mounted to rack 16 for concurrent movement between the
retracted and extended positions. Depending on the particular
configuration of upper rack 16 and its construction, the actual mounting
of these elements to upper rack 16 can greatly vary in accordance with
the invention. In any case, when upper rack 16 is in the retracted
position, it should be recognized that port extensions 161 and 162 extend
through respective openings 197 in cover member 195, as well as through
respective flapper valves 190 in flapper valve member 189 in order to
provide flow communication from first and second tubes 118 and 122 into
manifold 180. Cover member 195 is provided with upper and lower sets of
openings 197 in the manner corresponding to flapper valve member 189 due
to the ability of upper rack 16 to be vertically adjusted through
adjustment mechanism 17. Therefore, at any given time, port extensions
161 and 162 will either be received in the upper pair of openings 197 or
the lower pair of openings 197. In either case, whether the upper rack 16
is in the raised or lowered position, fluid flowing from port extensions
161 or 162 will be directed into a respective side of manifold 180 due to
the presence of internal divider 252. That is, as can best be understood
by reviewing FIGS. 4 and 6, any washing fluid flowing through port
extension 161 will be exposed to port 186 of manifold 180 and therefore
will be delivered to first upper spray arm 202 and, correspondingly,
intermediate spray arm 48. On the other hand, fluid flowing through port
extension 162 will be delivered on the other side of internal divider 252
of manifold 180 and will be exposed to port 185, thereby leading to
second spray arm 213. In addition to providing washing fluid to first
upper spray arm 202, first tube 118 is also fluidly connected to upright
tube extension 132 as perhaps best shown in FIG. 5. Therefore, a portion
of fluid flowing through first tube 118 will be directed to first upper
spray arm 202 so long as upper rack 16 is in the retracted position
whereby manifold 180 is interengaged with coupling 158, while some of the
flow through first tube 118 also bypasses tube extension 161 and flows
into upright tube extension 132, followed by horizontal tube extension
133 and then to upper spray arm 49. In order to ensure proper
registration between manifold 180 and coupling 158, ears 168 and 169 of
coupling 158 extend within lobes 256 and 257 or lobes 258 and 259
depending on the vertical height of upper rack 16 and, in fact,
preferably loosely engage onto manifold 180. In this manner, the force of
washing fluid flowing through either of port extensions 161 and 162
cannot shift upper rack 16 away from coupling 158.

[0033] Reference will now be made to FIG. 8 in describing a preferred
construction, mounting and operation of exterior corner nozzle 242 and
interior corner nozzle 249. With the particular mounting arrangement
associated with T-connector 219 of second spray arm 213, first leg 237 of
each angled flow tube 235 is basically positioned outside or at the
forwardmost kitchenware support region of upper rack 16. With the
arrangement of first leg 237 and second leg 238, as well as the corner
positioning of exterior corner nozzle 242, exterior corner nozzle 242 is
advantageously positioned to enable washing fluid to be sprayed onto the
outside surfaces of objects placed in the corners of upper rack 16. As
illustrated in FIG. 8, each exterior corner nozzle 242 includes an
upstanding portion 284 that leads to a top portion 285. Each top portion
285 is provided with an opening 287 from which extends a side slit 289.
At this point, it should be recognized that, since upper rack 16 is
generally rectangular in configuration and intermediate spray arm 48
rotates in a circular fashion, kitchenware placed in the corners of upper
rack 16 are more likely to have a lower amount of washing fluid directed
thereon during an overall washing operation. With the inclusion of second
spray arm 213, washing fluid can be strategically directed to these
corner portions of upper rack 16 in order to assure an adequate supply of
washing fluid being sprayed upon kitchenware at these locations. Based on
the location of exterior corner nozzle 242, washing fluid sprayed by
exterior corner nozzle 242 is preferably directed inward at kitchenware
on upper rack 16 and, assuming that certain kitchenware is provided in
the associated corner, an outer surface of the kitchenware will be
directly sprayed. Exterior corner nozzle 242 actually acts in conjunction
with interior corner nozzle 249 to ensure an adequate spray in these
regions. As shown, interior corner nozzle 249 preferably has associated
therewith a base 293 from which projects a cap member 294. Cap member 294
has a top portion 295 provided with a slot 296 having an enlarged central
open portion 298. Extending from cap member 294 is a support wall 300 and
extending from base 293, at a position spaced from support wall 300, is a
leg 301 from which is formed a flexible flange 302. As clearly shown in
this figure, a wire of upper rack 16 is received between support wall 300
and spaced leg 301 and is snapped beneath flexible flange 302 in order to
further support interior corner nozzle 249 directly from upper rack 16.

[0034] With this construction, washing fluid flowing into flow tube 216
will be bifurcated at T-connector 219, leading to both frontal exterior
corner nozzles 242 and interior corner nozzles 249. Although shown only
along frontal wall portion 139 of upper rack 16, it should be understood
that second spray arm 213 could also extend to other corner portions of
upper rack 16. For this purpose, FIG. 3 shows in phantom a potential side
extension tube at 310. FIG. 3 also particularly illustrates how a certain
piece of kitchenware can be advantageously cleaned through the use of
exterior corner nozzle 242 and interior corner nozzle 249. As
illustrated, a drinking glass or other container 315 is inverted over an
interior corner nozzle 249. During particular portions of a washing
operation when washing fluid is directed into second tube 122 and second
spray arm 213 so as to reach exterior corner nozzles 242 and interior
corner nozzles 249, the washing fluid will be sprayed directly within
glass 315 so as to hit an interior annular surface 317 of glass 315 from
interior corner nozzle 249. Simultaneously, the outermost exterior
surface 320 of glass 315 will be directly sprayed by exterior corner
nozzle 242. Therefore, instead of relying upon external surface 320 of
glass 315 being washed by fluid which hits portions of tub 5 and are
deflected onto exterior surface 320, exterior corner nozzle 242 will
directly wash these surface portions. Of course, the particular spray
arrangements and pattern can be readily adjusted by reconfiguring the
slots and/or openings associated with exterior corner nozzle 242 and
interior corner nozzle 249. In addition, further nozzles can be provided
along first leg 237 to provide additional spraying patterns from exterior
locations and, again, the flow path can be extended through the use of
side extensions 310. In order to enhance the fluid spray pressure and
spray efficiencies, it is preferred in accordance with the present
invention to time the flow of washing fluid through first and second
tubes 118 and 122 such that spray arms 48 and 49 will be provided with
washing fluid from first tube 118 during certain periods of the washing
operation and, at different times of the overall washing operation, the
fluid supply to first tube 118 will be cut off and instead fluid will
flow through second tube 122 so as to reach second spray arm 213. Again,
variations in the spray pattern and timing can be easily controlled
through suitable valving, such as through the use of diverter valve unit
126. Overall, providing the multi-tube fluid supply, mounting of manifold
180 to move with rack 16, providing both first upper spray arm 202 and
second spray arm 213 on rack 16 and/or arranging both interior and
exterior nozzles in corners of the rack provides for a more efficient and
synergistic washing result in connection with cleaning a wide range of
dishware placed upon rack 16 during a washing operation.

[0035] Although described with reference to preferred embodiments of the
invention, it should be readily understood that various changes and/or
modifications can be made to the invention without departing from the
spirit thereof. In general, the invention is only intended to be limited
by the scope of the following claims.